Green synthesis as an alternative technique for bioproduction of metallic nanomaterials has presented a great interest due to the composition of reducing agents in plants, bacteria, and fungi that favor the production of nanostructured materials. In this investigation, the extract of Thuja Orientalis was used to evaluate the synthesis of copper nanoparticles. The species presents biomolecules which make it a candidate for the reduction of metal ions. The FTIR analysis showed the presence of functional groups OH, CH, C=O, COOH, -OCH3, C-O-C proper to polyphenols, terpenes, and ligands. The kinetics of CuNPs synthesis was analyzed by UV-vis in which a narrow absorbance band was shown at 400 nm after 20 minutes of reaction using a concentration of precursor agent of 50 mM, giving us indications of a homogeneous system of nanoparticles, which was corroborated by SEM obtaining a particle size between 5-60 nm with a spherical morphology. By cyclic voltammetry, the reducing power of the extract against the ions of Cu+2 to Cu0 was demonstrated, as well as its tendency to oxidation, which can have great advantages in different applications.

In this research project, silver nanoparticles (AgNPs) were synthesized by green chemistry techniques. The extract of the leaves of the Ricinus communis species was used at different mass/volume concentrations of 0.25, 0.5, and 0.75% as a reducing agent, and AgNO3 was used as a precursor agent for Ag+1 ions at different concentrations (10, 20, and 30 mgL-1). The kinetics were followed at times of 10 to 50 minutes with intervals of 10 minutes. The extract was characterized by FTIR, finding the functional groups among which are OH secondary alcohols, phenols, C = O, to which the ability to bioreduce Ag+1 to Ag0 ions is attributed. The obtaining of the nanoparticles was characterized by UV-visible spectroscopy at the different times of addition of the precursor solution, finding the characteristic plasmon at 400 nm with the best results with the extract concentration 0.75% mass/volume and 30 mgL-1 of precursor solution in time of 50 minutes.

Nanoparticles exhibit localized surface plasmons as a direct consequence of size. This study focuses on photochemical synthesis through the irradiation of white LED light at different ranges of wavelengths: blue, green, and red. This technique allows a rapid synthesis to obtain colloidal silver nanoparticles using Sedum Praealtum extract as a reducing and stabilizing agent, and AgNO3 (20 mgL-1) as a precursor agent. The experimentation was carried out for each color, in times of 1, 2, and 3 hours. The colloidal solutions obtained from the synthesis were analyzed by UV-Vis spectroscopy, obtaining favorable results with blue radiation in a time of 2 hours, since the characteristic plasmon was observed at 421 nm with an absorbance of 0.15 au.